Each base station of a communication system radiates within a cell, and consequently, talks to all the telephones situated in this cell. When the user of a telephone moves and reaches the border of a cell, the base station can decide, depending on specific parameters measured by the telephone, to hand the telephone over to another base station.
Estimation of the speed of movement of the mobile telephone is a parameter which may be taken into account by the base station in deciding whether to transfer to another base station. Estimation of the speed can also be used to improve the monitoring of the reception power of the signal.
European Patent Application No. 1,014,107 discloses a method of estimating the speed of movement of a cellular mobile telephone. This method is based on an autocorrelation of the filtered power of the signal received. However, such a method is sensitive to the characteristics of the transmission channel, and in particular, to the number of coefficients of its impulse response. Furthermore, this method allows only binary information to be obtained, namely whether the mobile terminal is moving at low-speed or high-speed.